Dear Jack,  Regarding your inquiry, you'll have to check out the book,
"Treasures of Mechanical Music", by Arthur A. Reblitz and Q. David
Bowers, (C) 1981 by Vestal Press.  Go to page 472 for the B.A.B. 66-key
trackerbar scale.  (It will be the first of two 66 key scales, as the
second appears to only have one trackerbar hole for the snare drum.)

Hope this helps,

D.F. Rowe
Bronx, New York